In this multidisciplinary program investigators from The University of Chicago will be using positron emission tomography to measure regional blood flow and metabolism in the brain. Participants from the behavioral and biological sciences include investigators from radiological science, pharmacology and physiology, neurology, psychiatry, and biopsychology. The program consists of a scientific core integrated with four component research projects. The scientific core is the central resource which provides the technology and methods to measure blood flow and metabolism. The principle approach will be to use radioactive molecular oxygen and water. In addition, glucose metabolism will be studied using a radioactive analog and subsequently native-labeled glucose itself. One scientific project is committed to methodological studies using new approaches and new radiotracers for application in the clinical science studies. In these projects our first endeavor will be to describe flow and metabolism in normal and control subjects under baseline minimally stimulated conditions to define normal variance. We will determine the quantitative changes which occur regionally when brain function is initiated by various psychological and physiological perturbations including sleep. The effects of selected neuroactive drugs upon brain function will also be measured. Using these studies as a basis, we will examine how brain function is organized regionally and hemispherically. We intend to determine how regional brain function is altered in pathological conditions. Patients with behavioral disturbances in which changes at the anatomic level are absent and a second group with neurological impairment associated with neuronal death have been chosen. Neurotransmitter dysfunction is known or postulated to occur in both groups. The major long-term objective of this program is to determine the blood flow and metabolic correlates of regional brain function in health and disease.